 /*******************************************************************************
  * Copyright (c) 2000, 2004 IBM Corporation and others.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Common Public License v1.0
  * which accompanies this distribution, and is available at
  * http://www.eclipse.org/legal/cpl-v10.html
  *
  * Contributors:
  * IBM Corporation - initial API and implementation
  *******************************************************************************/
 package org.eclipse.core.internal.watson;

 import org.eclipse.core.internal.dtree.AbstractDataTreeNode;
 import org.eclipse.core.internal.dtree.DataTreeNode;

 /**
  * An <code>ElementSubtree</code> is a simple datastructure representing the
  * contents of an element tree. It can be used for rapidly creating ElementTree
  * objects, but cannot be treated as an ElementTree itself.
  * @see ElementTree(ElementSubtree)
  * @see ElementTree#getElementSubtree()
  */
 class ElementSubtree {
     protected String elementName;
     protected Object elementData;
     protected ElementSubtree[] children;

     static final ElementSubtree[] EMPTY_ARRAY = new ElementSubtree[0];

     /**
      * Creates an <code>ElementChildSubtree</code> with the given element name and element,
      * and child elements (organized by type).
      * Passing either null or an empty array for childTypes indicates no children.
      */
     public ElementSubtree(String elementName, Object elementData, ElementSubtree[] children) {
         if (children == null || children.length == 0) {
             children = EMPTY_ARRAY;
         }
         this.elementName = elementName;
         this.elementData = elementData;
         this.children = children;
     }

     /**
      * Creates an <code>ElementSubtree</code> from a (complete) element node.
      */
     ElementSubtree(DataTreeNode childNode) {
         AbstractDataTreeNode[] childNodes = childNode.getChildren();
         if (childNodes.length == 0) {
             children = EMPTY_ARRAY;
         } else {
             ElementSubtree[] types = new ElementSubtree[childNodes.length];
             for (int i = childNodes.length; --i >= 0;) {
                 types[i] = new ElementSubtree((DataTreeNode) childNodes[i]);
             }
             children = types;
         }
         elementName = childNode.getName();
         elementData = childNode.getData();
     }

     /**
      * Returns the child subtrees.
      * Returns null if there are no children.
      */
     public ElementSubtree[] getChildren() {
         return children;
     }

     /**
      * Returns the element data.
      */
     public Object getElementData() {
         return elementData;
     }

     /**
      * Returns the element name.
      */
     public String getElementName() {
         return elementName;
     }

     /**
      * For debugging purposes
      */
     public String toString() {
         return "ElementSubtree(" + elementName + ", " + elementData + ")"; //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
 }
 }
